Acid-resisting cement.



couPosmows, COATING 0R PLASTIC.

ot/gi MQM ALFRED EWART HOLLEY AND HARRY WILLIAM WEBB, OF OLDBUBY, ENG-LAND, ASSIGNOBS TO CHANGE & HUNT, LIMITED, OF OLDBUBY, ENGLAND.

' aom-nnsrs'rmo CEMENT.

No Drawing.

known cements to increase t ei idity of setti Th proportion of the lead carbonate added may vary within wide limits according to the rate of setting desired.

For example, a cement consisting of a mixture of eight parts by weight of finel round stoneware seven parts by we g it o sand "anfiwo parts of less finel round we IT- T? rick moistened with t ree par s y welg 1 o a 60 Twaddell sodium silicate solution cannot be used for or inary u1 mg purposes as it sets too slowlyg'if, however,

about 0.5 parts by weight of lead carbonate be mixed with the solids be ore a mg 10 silicate solution it can be so used.

The cement should be used within an hour of making up and no water or steam should be allowed to come into contact with either the solid constituents forming the cement or Specification of Letters Patent.

Application filed March 26, 1918. Serial No. 224,799.

with the cement itself, until it is thoroughly dry and it is therefore desirable to subject the finished work for several days to a temperature of 100 C. or for a shorter time to a higher tempera ure.

Cements made in accordance with this invention are unaffected by mineral acids or mixtures thereof over a wide range of temperature and by sulfur dioxid or tri-oxid, nitrous gases, chlorin or sulfureted hydrogen; they are therefore particularly suitable for the erection of chimneys to take the acid fumes, for reaction and absorbing towers, for acid storage tanks, and in fact for all cases where a good acid resisting cement is required, and can be applied under suitable conditions.

What we claim is 1. An improved acid resisting cement comprising a compound containing the metal lead and the carbonic acid radical, acid resisting siliceous material and a solution of a silicate.

2. An improved acid resisting ,cement comprising a compound containing the metal lead and the carbonic acid radical, acid resisting siliceous material and a solution of sodium silicate.

In testimony that we claim the foregoing as our invention we have signed our names this 28th day of February, 1918.

ALFRED EWART HOLLEY. HARRY WILLIAM WEBB.

Copies of tlie patent may be obtained tor .ilve cents each, by addressing the Commissioner of Patents, Washington, D. 0. 

